What is the author's tone in That Used to Be Us: How America Fell Behind in the World It Invented and How We Can Come Back by Thomas L. Friedman?

The overall tone of the book is a plea for help for a once-great nation that is on the brink of becoming a second-rate nation. The title, "That Used to Be Us," tells of the greatness of America and how it got there. Although most of the book outlines what is wrong with America, the final section of the book provides specific ways in which America can reclaim its rightful place as the best and most-admired nation on earth.